Commit Graph

28 Commits

Author SHA1 Message Date
Werner Johansson 9f7898f3ca backlight: lp855x: Make sure props struct is zeroed
The driver occasionally got stuck in suspend mode or other strange
states as those parts of the props struct were never initialized.

Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-05 13:47:42 +01:00
Milo Kim fe009175ae backlight: lp855x: Use private data for regulator control
LP855x backlight device can be enabled by external VDD input. The
'supply' data is used for this purpose. It's kind of private data
which runs internally, so there is no reason to expose to the
platform data.

And devm_regulator_get() is moved from _parse_dt() to _probe().
Regulator consumer(lp855x) can control regulator not only from DT
but also from platform data configuration in a source file such
like board-*.c.

Signed-off-by: Milo Kim <milo.kim@ti.com>
Acked-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:40:44 +01:00
Sean Paul 61c1c6147f backlight: lp855x: Don't clear level on suspend/blank
Don't clear the backlight level when we're going into suspend or
blanking. Instead, just temporarily set the level to 0 so we retain
the value when we resume.

Reported-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-06-23 15:47:33 +01:00
Sean Paul 829b030e58 backlight: lp855x: Add supply regulator to lp855x
This patch adds a supply regulator to the lp855x platform data to facilitate
powering on/off the 3V rail attached to the controller.

Cc: Stéphane Marchesin <marcheu@chromium.org>
Cc: Aaron Durbin <adurbin@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Acked-by: Bryan Wu <cooloney@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-12-09 09:24:45 +00:00
Sean Paul 47726656dd backlight: lp855x: Refactor DT parsing code
This patch refactors the dt parsing code to avoid setting platform_data,
instead just setting lp->pdata directly. This facilitates easier
probe deferral since the current scheme would require us to clear out
dev->platform_data before deferring.

Cc: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-12-09 09:24:42 +00:00
Jingoo Han a94cb12604 backlight: lp855x: Add blank line after declarations
Fixed the following checkpatch warning.

  WARNING: Missing a blank line after declarations

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-08-29 08:25:44 +01:00
Andrzej Hajda a5d8e2e73c backlight: Remove trivial get_brightness implementations
Since backlight core returns props.brightness in case get_brightness
is not implemented trivial implementations are not needed anymore.

Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-23 13:24:22 +01:00
Jingoo Han 2ce2386072 backlight: lp855x: remove unnecessary parentheses
Remove unnecessary parentheses in order to fix the following checkpatch
error.

  ERROR: return is not a function, parentheses are not required

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:36:57 -08:00
Jingoo Han 6255e8e984 backlight: lp855x: use devm_backlight_device_register()
Use devm_backlight_device_register() to make cleanup paths simpler.  Also,
unnecessary lp855x_backlight_unregister() is removed.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:18 +09:00
Jingoo Han c512794cad backlight: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to
make the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:16 +09:00
Milo Kim 5812c13a4e backlight: lp855x_bl: support new LP8555 device
LP8555 is one of the LP855x family devices.

This device needs pre_init_device() and post_init_device() driver
structure.  It's same as LP8557, so the device configuration code is
shared with LP8557.  Backlight outputs are generated from dual DC-DC boost
converters.  It's configurable EPROM settings which are defined in the
platform data.

Driver documentation and device tree bindings are updated.

Signed-off-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:14 +09:00
Shingo Nakao 9f0a511f4a backlight: lp855x: set zero brightness at FBBLANK
When backlight turns on early from display, a white line can be
seen on the screen. Therefore make sure backlight is off when we
are under an fb blank event.

Signed-off-by: Shingo Nakao <shingo.x.nakao@sonymobile.com>
Cc: Milo Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Oskar Andero <oskar.andero@sonymobile.com>
Acked-by: Milo Kim <milo.kim@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2013-07-26 11:44:51 +03:00
Kim, Milo 4add06645a backlight: lp855x: add a device tree structure
Enable supporting the DT structure of LP855x family devices.  If the
platform data is NULL, the driver tries to parse a DT structure.  Then,
the platform data is copied from the DT.  Documentation is added as well.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:19 -07:00
Kim, Milo c365e59d47 backlight: lp855x: remove duplicate platform data
The 'load_new_rom_data' was used for checking whether new ROM data should
be updated or not.

However, we can decide it with 'size_program' data.  If the size is
greater than 0, it means updating ROM area is required.  Otherwise, the
default ROM data will be used.  Therefore, this duplicate platform data
can be removed.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:19 -07:00
Kim, Milo 0b81857339 backlight: lp855x: move backlight mode platform data
The brightness of LP855x devices is controlled by I2C register or PWM
input .  This mode was selected through the platform data, but it can be
chosen by the driver internally without platform data configuration.

How to decide the control mode:
  If the PWM period has specific value, the mode is PWM input.
  On the other hand, the mode is register-based.
  This mode selection is done on the _probe().

Move 'mode' from a header file to the driver private data structure,
'lp855 x'.  And correlated code was replaced.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:18 -07:00
Kim, Milo 600ffd33d0 backlight: lp855x: convert a type of device name
Configurable data, backlight device name is set to constant character type.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:18 -07:00
Kim, Milo 6a7aeb1ae8 drivers/video/backlight/lp855x_bl.c: use PAGE_SIZE for the sysfs read operation
sysfs allocates PAGE_SIZE.  It is used by each R/W operation method.  Use
it instead of another buffer size.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:17 -07:00
Devendra Naga 9703542815 drivers/video/backlight/lp855x_bl.c: fix compiler warning in lp855x_probe
While doing with make W=1 gcc (gcc (GCC) 4.7.2 20121109 (Red Hat
4.7.2-8)) I found

  drivers/video/backlight/lp855x_bl.c: In function `lp855x_probe':
  drivers/video/backlight/lp855x_bl.c:342:35: warning: variable `mode' set but not used [-Wunused-but-set-variable]

fixed by removing it as since its not used anywhere

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Acked-by: Milo Kim <milo.kim@ti.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:15 -07:00
Kim, Milo 9e9cdc8969 backlight: lp855x_bl: simplify bl_get_brightness()
Getting the brightness value is not critical, no need to read the actual
register value.  To simplify it, just return the 'bl->props.brightness'
value.  Then, lp855x_read_byte() can be removed, not used any more.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21 17:22:25 -08:00
Kim, Milo 26e8ccc223 backlight: lp855x_bl: support new LP8557 device
LP8557 is one of LP855x family device, but it has different register map
and initialization process.  To support this device, device specific
configuration is done through the lp855x_device_config structure.

Few register definitions are fixed for better readability.
  BRIGHTNESS_CTRL -> LP855X_BRIGHTNESS_CTRL
  DEVICE_CTRL     -> LP855X_DEVICE_CTRL
  EEPROM_START    -> LP855X_EEPROM_START
  EEPROM_END      -> LP855X_EEPROM_END
  EPROM_START     -> LP8556_EPROM_START
  EPROM_END       -> LP8556_EPROM_END

And LP8557 register definitions are added.  New register function,
lp855x_update_bit() is added.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21 17:22:25 -08:00
Kim, Milo 68853bc2b3 backlight: lp855x_bl: introduce device configuration flow
At this moment, LP855x device driver has fixed register configuration.
For example, fixed register addresses and values are set on the device
initialization.  But new device of LP855x family, LP8557 has different
register map and initialization sequence.  To support new device
architecture, initialization process should be changed.

 Introduce new structure: lp855x_device_config
 =============================================
 With lp855x_device_config, device specific features are configurable.
 Use configurable function calls and register addresses rather than fixed values.

 Change on device initialization
 ===============================
 In old LP855x driver architecture, the device initialization was simple.
 - Just update the brightness/device control register/ROM area(optional).
 In new LP855x driver architecture, two more works are added - pre_init and
 post_init.
 Those init functions are optional, used for new device LP8557.

 New device initialization flow: generic sequence
 =================================================
 1) pre_init_device()
 2) update the brightness register
 3) update the device control register
 4) update ROM area if need
 5) post_init_device()

 Name change
 ===========
 Use generic name 'lp855x_configure()' instead of 'lp855x_init_registers()'.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21 17:22:25 -08:00
Kim, Milo eaa4d02fba drivers/video/backlight/lp855x_bl.c: remove unnecessary mutex code
The mutex for accessing lp855x registers is used in case of the user-space
interaction.  When the brightness is changed via sysfs, the mutex is
required.  But the backlight class device already provides it.  Thus, the
lp855x mutex is unnecessary.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:16 -08:00
Kim, Milo 8cc9764c9c drivers/video/backlight/lp855x_bl.c: use generic PWM functions
The LP855x family devices support the PWM input for the backlight control.
 Period of the PWM is configurable in the platform side.  Platform
specific functions are unnecessary anymore because generic PWM functions
are used inside the driver.

(PWM input mode)
To set the brightness, new lp855x_pwm_ctrl() is used.
If a PWM device is not allocated, devm_pwm_get() is called.
The PWM consumer name is from the chip name such as 'lp8550' and 'lp8556'.
To get the brightness value, no additional handling is required.
Just the value of 'props.brightness' is returned.

If the PWM driver is not ready while initializing the LP855x driver, it's
OK.  The PWM device can be retrieved later, when the brightness value is
changed.

Documentation is updated with an example.

[akpm@linux-foundation.org: coding-style simplification, per Thierry]
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:16 -08:00
Bill Pemberton 7e4b9d0bb2 backlight: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:06:39 -08:00
Bill Pemberton d1723fa266 backlight: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:03:45 -08:00
Kim, Milo f7f9505677 backlight: move lp855x header into platform_data directory
The lp855x header is used only in the platform side, so it can be moved
into platform_data directory

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:15 -07:00
Kim, Milo a1fcb2e318 backlight: move register definitions from header to source
ROM boundary definitions do not need to be exported because these are
used only internally in the lp855x driver.

And few code cosmetic changes

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:15 -07:00
Kim, Milo 7be865ab86 backlight: new backlight driver for LP855x devices
THis driver supports TI LP8550/LP8551/LP8552/LP8553/LP8556 backlight
devices.

The brightness can be controlled by the I2C or PWM input.  The lp855x
driver provides both modes.  For the PWM control, pwm-specific functions
can be defined in the platform data.  And some information can be read
via the sysfs(lp855x device attributes).

For details, please refer to Documentation/backlight/lp855x-driver.txt.

[axel.lin@gmail.com: add missing mutex_unlock in lp855x_read_byte() error path]
[axel.lin@gmail.com: check platform data in lp855x_probe()]
[axel.lin@gmail.com: small cleanups]
[dan.carpenter@oracle.com: silence a compiler warning]
[axel.lin@gmail.com: use id->driver_data to differentiate lp855x chips]
[akpm@linux-foundation.org: simplify boolean return expression]
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:33 -07:00